Computed tomography assessment of maxillary sinus hypoplasia and associated anatomical variations: a systematic review and meta-analysis of global evidence.

Objective: To summarize the scientific evidence on the prevalence of maxillary sinus hypoplasia (MSH) and associated anatomical variations as assessed by computed tomography scans.

Study design: This PROSPERO-registered systematic review followed the recommendations of the PRISMA guidelines. Search algorithms were constructed for each of the six databases and gray literature. After screening the references (Rayyan^®), the extracted data were meta-analyzed according to a random-effects model. The joanna briggs critical appraisal tool assessed the methodological quality of the included studies. The GRADE approach was used to estimate the certainty of the evidence.

Results: From a total of 2781 studies screened, 22 were considered for four meta-analysis. The prevalence of MSH in 7358 patients was 5.65% (CI95% = 4.07-7.47%) with significant heterogeneity between studies (p < 0.001, I² = 89.30%). MSH was identified in 295 patients, of whom 82.38% (CI95% = 75.82-88.09%) had unilateral hypoplasia and 17.62% (CI95% = 11.91-24.18%) bilateral hypoplasia with moderate heterogeneity between studies (p < 0.0503, I² = 42.87%). The prevalence of MSH in 9998 maxillary sinuses was 3.77% (95% CI = 2.44-5.38%), with significant heterogeneity between studies (p < 0.001, I² = 92.84%). Hypoplastic/aplastic uncinate process, concha bullosa and paradoxical concha were the most reported anatomical variations. The studies presented a low-moderate methodological quality. The certainty of the evidence was very low to moderate.

Conclusion: The prevalence of maxillary sinus hypoplasia observed was 5.65%, with most cases being unilateral.